In May, Yuya Ino, a 23-year-old resident of Kitakyushu City, Fukuoka Prefecture, Katuyosi Hayakawa, 22, and three other persons, allegedly broke into the residence of a 73-year-old woman in the Mukojima area of Sumida Ward.

After threatening to kill the woman if she made noise, they stole 190,00 yen in cash contained in a safe and a bag.

Ino, Hayakawa and one other suspect, who have bee accused of robbery, admit to the allegations. The other suspects deny the charge, with one saying he only served as a lookout.

Police first arrested Hayakawa over a separate incident that also took place in May. Police believe that the suspects are members of a nine-person ring behind a number of purse-snatching and robbery incidents in Kanto and Kyushu.